Praktica battery problems?

[Coldkennels]

I have somehow acquired two different Praktica bodies - an MTL3 and a Super TL. Both came into my possession with Alkaline batteries in them, and the MTL light meter was originally dead-on, although the Super TL was always underexposing by two stops (from what I gather, a common problem with using alkaline batteries in circuits designed for mercury ones).

Since then, the MTL3 has developed the same problem as the Super TL. According to every source I can find, both of these cameras are supposed to have "bridge circuits", and the different voltage shouldn't affect them. The batteries are still producing 1.5v, so that can't be the source of the problem. So why would the meter go from accurate to two stops out almost overnight? And what on earth can I do to rectify it?

 

[Penny Lane]

This thread over at the neighbours shows a wiring diagram for the Praktica L-series with stop down metering: http://photo.net/classic-cameras-forum/00QTcl?start=20 (page three, bottom). Maybe there's one of the three potentiometers on the bottom PCB that acts up, or the large one that tells the meter the chosen shutter speed. Also check if that pot is lined up correctly (even if it shouldn't be able to go anywhere)

Also be sure all wiring and the meter's PCB are in good condition, I've had a few that were rotted out due to spilled battery acid. I did a PCB-replacement once in an LTL3 with a PCB out of a junk MTL5B. It can be done, but I found it fiddly.

Hope this helps, and hope someone else here has even better ideas 😎

Derk

 

[Drago]

Yes - they work with 1.5v batteries - at least my works just fine. The solution to your problem is to buy new praktica i guess. Even mint one, with everything working perfectly is dirty cheap

 

[Coldkennels]

Yes - they work with 1.5v batteries - at least my works just fine. The solution to your problem is to buy new praktica i guess. Even mint one, with everything working perfectly is dirty cheap

Bit wasteful, don't ya think?

I'm sure there must be a way to get it back to spec, even if it does mean tinkering with the pots. Cheers for the link, Derk.